html { color-scheme: light dark; }
h1 { font-family: 'IBM Plex Sans';font-size: 50px; 
text-align: center;}
body { width: 35em; margin: 0 auto;
font-family: 'IBM Plex Sans';font-size: 22px; 
text-align: center;}
a:link, a:visited {
  border: 2px solid #00ffff;
  background-color: #4e4e4e;
  color: #00ffff;
  padding: 14px 28px;
  width: 50%;
  font-size: 16px;
  cursor: pointer;
  border-radius: 32px;
  text-align: center;
  text-decoration: none;
  transition-duration: 0.4s;
  margin: 4px 2px;
  display: inline-grid;
}
a:hover, a:active {
  background-color: #00ffff;
  border: 2px solid #00ffff;
  color: #4e4e4e;
}